ON THE western fringes of Siberia, the Stone Age Denisova cave has surrendered precious treasure: a toe bone that could shed light on early humans’ promiscuous relations with their hominin cousins.

New Scientist has learned that the bone is now in the care of Svante Pääbo at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who revealed the first genetic evidence of interbreeding between ancient humans and other hominins (New Scientist, 30 July, p 34).

It is a very exciting discovery, says Isabelle De Groote at London’s Natural History Museum. “Hominin material from southern Siberia is rare and usually extremely fragmentary.”

The primitive morphology of the 30,000 to 50,000-year-old Denisovan finger bone and tooth indicates that Denisovans separated from the Neanderthals roughly 300,000 years ago. At the time of the analysis, Pääbo speculated that they came to occupy large parts of east Asia at a time when Europe and western Asia were dominated by Neanderthals. By 40,000 years ago, Homo sapiens was also moving around much of the region. But the Denisovans remain known only from the finger and tooth fossils – not enough information to formally assign them to their own species.

That may change with analysis of the newly discovered toe bone. It was found in the same layer of the cave floor as the finger bone, by Maria Mednikova at the Russian Academy of Sciences in Moscow (Archaeology, Ethnology and Anthropology of Eurasia, vol 39, p 129).

Mednikova says this suggests it belonged to a contemporary individual, alive roughly 40,000 years ago. But her studies show the finger and toe bones belonged to distinct people. In addition, the toe bone is stocky and its shape is somewhere between that of a modern human and a typical Neanderthal.

Others are less convinced. Erik Trinkaus at Washington University in St Louis, Missouri, who has written extensively on hominin foot bone morphology, says the bone’s sturdy appearance is interesting but inconclusive from a taxonomic perspective.

What’s needed is DNA evidence. For now, though, Pääbo’s team remain very tight-lipped about what, if anything, they have found. “We have no results we are ready to talk about yet,” Pääbo told New Scientist.

Not just a Neanderthal crush: modern humans interbred with more archaic hominin forms while in Africa: here. And here.

IT LOOKS like Neanderthals may have beaten modern humans to the seas. Growing evidence suggests our extinct cousins criss-crossed the Mediterranean in boats from 100,000 years ago – though not everyone is convinced they weren’t just good swimmers: here.

Humans reached Asia in two waves: Some early migrants interbred with mysterious Neandertal sister group: here.

European neanderthals were on the verge of extinction even before the arrival of modern humans: here.

A jawbone and its teeth discovered in a South England cave, Kent’s Cavern, in 1927 is more than 41,000 years old, suggests new dates linked to animal remains in the same cave. Meanwhile, two teeth excavated from a southern Italian site, Grotta del Cavallo, in the 1960s and attributed to Neanderthals may instead belong to modern humans. At 43,000 to 45,000 years old, they are the oldest anatomically modern human remains identified in Europe: here.

The discovery of stone axes in the same sediment layer as cruder tools indicates that hominins with differing tool-making technologies may have coexisted: here.

People love to get their hands on the latest and greatest technology, and scientists had long believed that early humans were no exception. Paleontologists theorized that our ancestors didn’t start leaving Africa until they had developed advanced hand axes. But a new study finds that early humans began to migrate out of the continent with more primitive tools even though better technology had been invented: here.

For years, evolutionary biologists have predicted that new human species would start popping up in Asia as we begin to look closely at fossilised bones found there. A new analysis of bones from south-west China suggests there’s truth to the forecast: here.

You could call it the original baptism of fire: the moment hominins first began controlling flames. There is now evidence that moment came at least 1 million years ago, a finding that will reignite the debate over whether human anatomy was changed forever by cooking: here.

9 thoughts on “Ancient Siberian hominin discovery”

Modern humans (Homo sapiens) last shared a common ancestor with two types of archaic hominins, Neandertals and Denisovans, roughly 800,000 years ago, and the population leading to modern H. sapiens separated from that leading to Neandertals and Denisovans roughly 400,000 years ago [1,2,3,4]. Genome sequences for these two types of archaic hominins have been reported [1,2]. They were determined by sequencing ancient DNAs using techniques that generated many short sequence reads. Here, we analyzed individual sequence reads used to assemble the published Neandertal and Denisovan genomes for insertions of Human Endogenous Retrovirus K (HERV-K) DNA. Virus–host DNA junctions were identified that defined 14 proviruses where modern humans contain the corresponding, empty, preintegration site. Thus, HERV-K reinfected germ lineage cells of Neandertals and Denisovans multiple times, and these events occurred around the time of or subsequent to the divergence of the archaic hominin lineages from that leading to modern humans. One of the proviruses was shared by Neandertals and Denisovans, which is consistent with the hypothesis that these archaic humans shared a common ancestor more recently than they shared one with the lineage leading to modern humans.